Apparatus for drying grains.



No. 713,859. r Patented Nov. l8. I902.

A. P. GRISWELLA A APPARATUS FOR DRYING GRAINS.

(Application filed June 7, 1902.)

l 2 Sheets-Sheet I' (No Model.

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Ho WASHINGTON n c Patented Nov. l8, I902.

A. P. CRISWELL. APPARATUS FOR DRYING GRAINS.

(Application filed June 7, 1902.)

(No Model.)

lltuTian ETaTns PATENT OFFICE.

ALEXANDER P. CRISl/VELL, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE- HALF TOJOHN M. WESTERLIN AND ALLAN CAMPBELL, OF THE FIRM OF IVESTERLIN &CAMPBELL, OF CHICAGO, ILLINOIS.

APPARATUS FOR DRYING GRAINS.

SPECIFICATION forming part of Letters Patent No. 713,859, dated November18, 1902.

Application filed June 7, 1902. Serial No. 110,616. (No model.)

To all whom it may concern.-

Be it known that I, ALEXANDER P. CRIS- WELL, a citizen of the UnitedStates, residing at Chicago, in the county of Cook and State ofIllinois, have invented new and useful Improvements in Apparatus forDrying Grains, of which the following is a specification.

My invention relates to improvements in drying apparatus for employmentin distilleries or other establishments where grain or any othermaterial is subjected in large quantities to a drying operation. Inapparatus for this purpose as commonly constructed the material to bedried is fed into one end of a drying-chamber and automatically stirredand advanced while being subjected to the drying action of currents ofair.

My object is to provide apparatus of this class of animprovedconstruction which gives to the apparatus comparatively great capacityand renders it particularly effective for its purpose, as well aseconomical to construct and operate.

In the drawings, Figure 1 is a broken sectional elevation of apparatusconstructed with myimprovements, the section being takenon line 1 inFig. 2 and viewed in the direction of the arrow; 2, an enlargedcross-section taken on line 2 in Fig. 1; Fig. 3, an enlarged brokensectional view of a rotary air-conduct ing pipe and branch pipes withone form of Valve mechanism; Fig. 4, asimilar view showing a modifiedform of the valve mechanism.

Ais the outer casing of the apparathsgvhich is formed, preferably, ofsheet or plate metal a and a heat-insulating lining or covering a. Thecasing is upon a skeleton frame consisting of uprights b b andcross-bars b I), resting upon brackets b on the uprights.

B, C, and D are longitudinally-extending cylinders or drying-chambersmounted one above the other in the frame and casing A, each beingsurrounded by a steam-jacket c. The cylinders 13, C, and D are formedwith the heads B C D extending through the end walls of the casing A andprovided with inlet and outlet pipe-sections d 6, respectively. Theinlet-pipe (Z of each cylinder, which is also an air-vent, extendsupward, while the outlet 6 at the opposite end extends from the lowerside thereof downward, and the outletpipes of the two upper cylindersare bolted to the inlet-pipes of the next lower cylinders in eachinstance, whereby the said cylinders and pipes form acontinuousconvoluted passage from the inletd of the uppermost cylinderto the outlet e of the lowermost cylinder.

E E E are rotary hollow shafts journaled at opposite ends in bearingsfinthe cylinderheads. At one end the shafts are provided with beveled gearwheels g, meshing with beveled gears g on a vertical shaft 9 driven to.rotate from any suitable source of power. The shaft g rests at itslower end in a seat It and is steadied by brackets h,extending from theframe of the casing A. At the end which carries the gear-wheel g eachshaft E is closed by a plug t'. At the opposite end of the casing andheld rigidly in place is an air-con ducting pipe F, provided with branchpipes F, which in the preferred construction communicate with tubes Fwhich extend through the bearings f and into the hollow shafts E topoints adjacent to the plugged ends 7). The tubes F are stationary andeach is formed on its under side witha longitudinal slot F (as shownmost plainly in Fig. 3,) extending nearly the full length of thecylinder. Surrounding the tubes F beyond the open ends of the shafts E,are stuffing-boxes f. On the shafts E are spiral series ofconveyor-blades E on radial tubes E open at their inner and outer ends.The tubes and blades extend nearly to the inner annular walls of thecylinder and the blades are set at an angle, as indicated. In the top ofthe casing A is an air-inlet G, and the pipe F communicates with thelower end of the casing at 70. Inter-posed in the pipe F is an air-pump7a, which may be in the form of a fan-blower. Communicating with thesteam-jacket c of each cylinder is a steam-supply pipe H, and extendingfrom the lower side of each steam-jacket is a steam exhaust or drip pipeII. In the casing A between the cylinders B and C is ahorizontally-extending partition or baffle-plate I, extending from oneend nearly to the opposite end, as shown, and between the cylinders Cand D is a similar partition or baffle-plate 1, extending from one endof the casing nearly to the other, as shown. The object of thebaffle-plates I I is to cause air entering at G to travel the fulllength of the cylinder B, then of the cylinder 0, and then of thecylinder D before it is withdrawn through the pipe at 7c.

In operation the shaft G is rotated to rotate the shafts E. Theconveyer-blades in the cylinders B D are so arranged that they conveyfrom left to right (in Fig. 1) while the blades in the cylinder 0 conveyfrom right to left. The material to be dried is fed by any suitablemeans into the opening d of the uppermost cylinder B and in the rotationof the conveyors it is moved the full length of the cylinder B, thendischarged through the pipe 6 into the end of the cylinder 0, thencaused to travel the full length of said cylinder,then discharged intothe cylinder D, and after traveling the full length of the lastnamedcylinder it is discharged through the outlet e of the cylinder D. Steamis caused to enter through the pipes H and fill the steam-jackets c tomaintain the cylinders hot. The air-pump is actuated to draw air throughthe opening 70 and discharge it into the branch pipes F. The air thuspumped is drawn into the casing at G, and traveling a zigzag coursethrough the casing is heated by the outer walls of the steam-jackets toa more or less high temperature. The tubes or hollow shafts E fitclosely around the inner stationary tubes F, and in their rotation theinner ends of the radial tubes E are closed by the valves formed by thetubes F in their movement across the upper sides of the latter andopened as they cross the slots F Thus the dry hot air entering the pipesF from the pipe F is discharged only through the downward-extendingpipes E to the lower parts of the dryingchambers, and this air beingforced from the under side upward through the mass of grain or othermaterial to be dried it penetrates the entire mass and quickly takes upthe moisture therefrom. The moisture-laden air rising through the massof grain or the like moves upward in the cylinders in the directioncontrary to the movement of the grain and escapes at the grain-inlet andair-vent d of the upper drying-chamber. The construction describedbesides rendering the apparatus compact causes it to be economical inthe use of steam, because practically all the heat of the steam isutilized, first, in heating the drying-chambers from the steam-jackets,and, secondly, in heating air at the outer sides of the steam-jackets,which is afterward discharged into the drying-chambers, as described.The effect of discharging the heated air into the lower parts only ofthe drying-chamber is to dry the mass of material quickly and soeffectively as to give the apparatus comparatively great capacity. Ifdesired, the air-induction means may be provided only in one, preferablythe lower, drying-chamber.

In Fig. 4 I have shown a modified construction of the means fordischarging the air only into the lower parts of the drying-chambers.

In this construction the rotating hollow shaft E is itself theair-conducting tube, communieating with the pipe F, and carries the radially-extending blade-carrying air-conducting tubes E. In the tubes Eadjacent to their inner ends are valves Z, pressed normally by springs Zagainst their seats to close in the direction of the tube E. The valvesl are upon stemsZ ,whichprojectintothetubesE. Inlieu of the slotted tubeF of the preferred construction a stationary bar G extendslongitudinally within the tube E and is shaped along its lower side witha cam-surface min the path of the valve-stems Z In the rotation of thetube E with its radial tubes and conveyorblades the valves Z are openedas the stems Z pass across the cam surface on and are closed by thesprings Z when they pass the said cam-surfaces. Thus, as in thepreferred construction, hot dry air from the pipe F is discharged intothe drying chamberor chambers only from the radial tubes as they extendin the downward direction, whereby the air is forced to the under sideof the mass of grain or the like to be dried.

Although my improved drying apparatus is designed more especially foruse as a graindrier, it is not to be limited to any particular use, andwhile I prefer to construct it throughout, as shown and described, itmay be variously modified in the matter of details of constructionwithout departing from the spirit of my invention, as defined by theclaims.

What I claim as new, and desire to secure by Letters Patent, is

1. In a drying apparatus, the combination of a drying-chamber having atone end an air-vent and inlet for the material to be dried, and havingat is opposite end an outlet for said material, means for stirring andconveying the material to be dried longitudinally through said chamberfrom said inlet to said outlet, a steam-jacket about said chamberconnected with a steam-supply, an air-chamber about said steam-jacket,and means for passing air through said air-chamber and discharging itinto the said drying-chamber, whereby the air passes through the saiddrying-chamber in the direction opposite to the direction of movement ofsaid material.

2. In a drying apparatus, the combination of a series of drying-chambersdisposed one above the other and forming an endless convoluted passagefor the material to be dried, means for stirring and conveying the saidmaterial successively through said chambers, a steam-jacket about. eachof said chambers connected with a steam -supply, a casing about all saidchambers forming an air-passage around said steam-jackets, an air-inlettoward one end of said air-chamber, an airoutlet toward the opposite endthereof, an air-conduit extending from said outlet to the interior ofsaid drying-chambers, and means for forcing air through said conduit,substantially as and for the purpose set forth;

3. In a drying apparatus, the combination of a drying-chamber, means forstirring and ing-chamber in the lower part of the mass of conveying thematerial to be dried longitusaid material therein, substantially as anddinally through said chamber, a steam-jacket for the purpose set forth.

about said chamber connected with a steam- ALEXANDER P. CRISWELL.supply, an air-chamber about said steam- In presence ofjacket, andmeansfor passingair through said ALBERT D. BACOI,

air-chamber and discharging it into said dry- ARTHUR MALDANER.

